Sewing machine



W. A. AYRES SEWING MACHINE Nov. 29, 1955 2 Sheets-Sheetl Filed Dec. 23, 1952 INVENTOR. Wnwewnx Axlyzes BY@ 4; g e 6% (%W.

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SEWING MACHINE 2 Sheets-Sheet? Filed Dec. 23, 1952 a. T: m? 5 2a INVENTOR. W4LOEMfl/P A-AyREs W M x {WWW Arr-012N575 United States Patent SEWING MACHINE Waldemar A. Ayres, Lakewood, Ohio, assignor to White Sewing Machine Corporation, Lakewood, (Bhio, a corporation of Delaware Application December 23, 1952, Serial No. 327,587

13 Claims. (Cl. 112210) This invention relates to a sewing machine and particularly to the feed mechanism thereof.

An object of the invention is to provide an improved and novel feed mechanism for a sewing machine whereby forward and reverse feed can be obtained while the amplitude of the feeding movement in each direction is infinitely variable within the capacity of the mechanism between zero and maximum.

Another object is to provide an improved and novel feeding mechanism which is of simple construction, efficient, quiet, and produces minimum vibration in operation and can be readily adjusted for direction and amplitude of feeding movement.

A further object is to provide an improved and novel feeding mechanism as referred to in the preceding objects and which mechanism is on and is actuated by a feed shaft beneath the bed of the sewing machine and which shaft may operate the rotary hook of the machine.

Another object is to provide in the feed mechanism of a sewing machine improved means for raising and dropping the feed dog including means for controlling the height of the feed dog whereby the dog can be adjusted to a plurality of positions from a drop feed position to a maximum raised position.

A still further object is to provide an improved and novel feed mechanism for a sewing machine whereby forward and reverse feed can be obtained while the amplitude of the feeding movement in each direction is infinitely variable within the capacity of the mechanism between zero and maximum and also the feed dog height can be controlled in a novel and efiective manner from a drop feed position to a maximum raised position.

Further and additional objectsand' advantages will become apparent hereinafter during the detailed description of an embodiment of the invention which is to follow and which. embodiment is illustrated in the accompanying drawings, wherein Fig..1 is av longitudinal sectional view through the bedplate of a sewing machine and showing beneath the bed plate the feeding mechanism, the rotating hook and the shaft for operating the same, a portion of the reciprocating needle bar and needle being shown above the bed plate in elevation and a portion of the vertical removable plate which closes the hand opening in .the.

bed plate and shows the feed dog that is mounted in an opening in the plate.

Fig. is a fragmentary sectional view taken substan- Patented Nov. 29, 1955 ICC tially on line 55 of Fig. 1 looking in the direction of the arrows.

Fig. 6 is a sectional view taken substantially on irregular line 66 of Fig. 1 looking in the direction of the arrows with certain portions broken way to reveal other portions in elevation, and

Fig. 7 is a fragmentary top plan view of that portion of the bed where the feed dog height control knob is located.

Referring to the drawing, 10 designates the bed plate of a sewing machine and it will be understood that the head of the machine is supported on the bed plate and includes a gooseneck having a vertical hollow arm, a portion of which is indicated at 11 and a horizontal arm overhanging the bed plate but not shown herein since it will be well understood in the art.

The free end of the horizontal arm of the head mounts the vertically reciprocating needle bar 12 which has clamped in its lower end the needle 13 that reciprocates through the elongated opening 14 in the feed dog 15 that is located in the feed dog opening 16 of a removable closure plate 17 that is supported by the bed plate- 10 and encloses a hand opening therein affording access to the rotary hook, the bobbin and other mechanism as will be well understood in the art. It will be understood also. that the horizontal arm of the gooseneck or head mounts a shaft which is operatively connected to the needle bar 12 to reciprocate the same and that said shaft is connected through a suitable operative connection. in the vertical arm 11 of the head, with the feed shaft 18 rotatably mounted in bearings beneath the bed plate 10 all as well known in the art and hencev not shown herein. In this particular instance the feed shaft 18 and the shaft in the horizontal arm of the head are operatively interconnected so as to rotate in a onc to-one relationship.

As viewed in- Fig.1, the left hand end of the feedshaft 18 is supported in a suitable bearing formed in a bracket 19 located beneath the bed plate and having a horizontal portion 19a. The shaft 18 has fixed to-it adjacent to the bracket 19 a bevel gear 20 that'meshes with a smaller bevel gear 21 fixed on the lower end of a stub shaft 22 that is vertically and rotatably mounted in a suitable bearing bushing arranged in the horizon tal portion 19a of the bracket. The stub shaft 22 is shown as formed integral with and centrally of the un-- derside of the rotary book 23 which contains the bobbin case 24 in which is located the bobbin 25. The

ratio of the gears 20 and 21 is such that the rotary horizontal portion 19a of the bracket and adjacent to the are provided with longitudinally extending slots 28 that slidably receive and support the projecting opposite ends of a rod 29. The rod 29 slidably projects through the upper end 30 of a cage memberwhich on one side (the right hand side as viewed in Fig. 3) is provided. with spaced parallel wall portions 31. The cage member is also provided intermediate its upper end 30 and its lower end 32 with a recess 33. The cage member projects into an opening in the bracket portion 19b, and the upper end 30 of the cage member extends into a horizontal.

I The parallel walls 31' have a're'duced vertical height so that their upper and lower edges terminate below and above the upper end of the portion 30 and the lower end-v of the portion 32. The wall portions 31 adjacent their free ends are provided with aligned vertically extending channels 36. It will be seen that the cage member can slide axially of the rod 29 and also that it can have a limited up and down movement due to the rod 29 being carried by the rockable arms 26.

The feed dog 15 is fixed to the horizontal arm 37 of a depending bracket arm 38, the lower end of which extends between the walls 31 of the cage and is fixedly secured to the cage by any suitable securing means, such as the screws shown in the drawing, hence the up and down movement and the horizontal cross movement of the cage just above referred to will be imparted to the feed dog in the form of a rise and fall movement and a linear feeding movement.

The shaft 18 extends through the cage intermediate the walls 31 and is provided with an elongated key 39 fixed in a key way in the shaft 18 by a clamping collar 39a and setscrew 391). A sleeve 40 is splined on the shaft 18 for movement axially thereof and rotation therewith by a spline groove receiving the key 39. The sleeve 40 is provided with a sleeve portion 40a of a reduced diameter and having fixed thereon an elongated cam member 41 which at one end abuts an external shoulder on the sleeve-4tl The sleeve 40 has anenlarged diameter portion 40b provided with an annular groove 42 receiving a straddling adjusting yoke 43 that is fixed to a longitudinally movable shaft 44 later to be referred to. The elongated cam- 41 has its axis of symmetry inclined relative to the axis of the bore therethrough and has its opposite ends 180 out of phase for a purpose later to be explained.

The cam 41 has fixed in its periphery an axially extended key 43a which slides in a key way formed in the central bore of a ring-like cam follower 41a which slidably fits the cam and which extends into the channels 36 in the walls 31 of the cage. It will be seen that when the sleeve 40 is moved axially of the shaft 18 so as to slide the cam 41 axially relative to the ring or cam follower 41a to the mid-position as shown in Fig. 1 that then rotation of the shaft 18 and cam 41 will impart only a true rotative movement to the ring 41a, and will not produce any lateral movement of the cage since the latter is concentric with the shaft 18. However, when the sleeve 40 is moved axially of the shaft to slide the cam 41 relative to the ring 41a to position the latter to one side or the other of center position, then the rotation of the cam will produce an eccentric movement in the ring, the vertical portion of which movement will be wasted while the horizontal portion thereof will impart movement of the cage transversely of the shaft 18, it being recalled that the upper portion 30 of the cage slides on the rod 29. It will be seen that when the ring 4101 is in a position on the cam 41 to one side or the other side of center position the eccentric movement of the ring will impart reciprocation to the cage transversely of the shaft 18. This reciprocation of the cage directly reciprocates the feed dog 15 and this reciprocation in conjunction with the rise and fall movement of the feed dog later to be described and the fact that the ends of the cam 41 are 180 out of phase provides for forward and reverse feeding movement of the feed dog.

As already stated, the yoke arm 43 which straddles the groove 42 in the sleeve 40 is fixed to one end of a shaft 44 and it will be noted that said shaft slides longitudinally in suitable supporting brackets 45 depending from the underside of the bed plate 10. The other end of the shaft 44 is of forked formation and mounts a pin 46. The pin 46 extends through a vertically elongated opening 47 in the lower end of a lever 48 that is located between the tines of the forked end of the shaft 44. The lever 48 pivots on a pivotpin 49 located above the pin 46 and carried by a depending lug 51) on the bed plate' 10. The lever arm above the pivot 49 passes through an opening 51 in the bed plate and above the latter and is provided at its upper end with a pointer 52. Below its upper end the lever 48 is provided with an opening through which extends the threaded shank 53 of a clamp ing screw, the head 54 of which is mounted in the curved channel formed in a fitting plate 55 secured to the vertical arm 11 of the sewing machine head with said channel facing the arm. A knurled clamping nut and operating handle 56 is screwed on the shank 53 of the clamping screw and it will be understood that when said nut is loosened the lever 48 can be rocked about its pivot to move the shaft 44 endwise to shift the sleeve 40 and vary the relationship between the cam 41 and ring 41a and when the desired relationship has been obtained then the nut can be screwed down to clamp the lever 43 in the selected position. The pointer 52 at the upper end of the lever 48 cooperates with an arcuate scale 57 formed on a portion of the fitting plate 55 and calibrated in terms of forward and reverse feeding movements.

In order to impart the rise and fall movement to the cage, bracket arm 38 and feed dog 15 the following arrangement is utilized.

A cam 58 is mounted on the main shaft 18 and is keyed to said shaft by the key 3? to rotate therewith. The cam 58 is located in an elongated opening 59 formed in a cam follower plate 60. The cam follower plate 59 is mounted in the recess 33 of the cage and is supported by the underside of the upper end 3 and the upper side of the lower end 32 of the cage for sliding movement transversely of the shaft 18. The elongated opening 59 in the cam follower plate St) is inclined vertically downwardly from its one end, wherefore the cam follower plate can be adjusted transversely of the shaft 18 to position the cam 58 in the high portion at said one end of the opening 59, in the low portion at the other end of the opening, or in an intermediate portion. It will be seen that as the position of the cam 58 approaches the high end of the opening 59 the cam follower plate 60 and the cage will be proportionately raised with the result that the feed dog 15 on the bracket arm 38 will be raised. Conversely, as the position of the cam 53 in the opening 59 approaches the low end of the opening the cam follower plate 60, and cage, the bracket 38 and the feed dog 15 will be proportionately lowered. When the cam 58 is in the highest portion of the opening 59 the feed dog will be raised to maximum position while when r the cam 58 is in its lowermost position in the opening 59 the feed dog will be lowered to a drop feed position, wherein it will exert no feeding action on the material being sewed.

It will be understood that the raised and lowered positions of the feed dog as just referred to mean those positions from which the rising movement of the feed dog commences, since Whatever the position of the cam 58 in the opening 59 the high point of the cam when engaging the upper side edge of the opening will raise the cage and the feed dog and when said high point of the cam engages the lower side edge of the opening a lowering of falling movement of the feed dog will be effected. The cam 58 will rotate at all times during the operation of the machine but it will be seen that when it is desired to render the feed dog inactive it can be positioned in an inactive or drop feed position by locating the cam 58 in the low end of the opening 59 as, for instance, when it is desired to do darning, embroidering or other similar operations where the material would be manually moved in a multitude of directions.

In order to adjust the location of the cam 53 in the opening 59 to adjust the height position of the feed dog from the drop feed or inactive position to maximum raised active position or to an intermediate active position the following mechanism is employed: One end of the follower plate 6! i. e., the left hand end thereof as viewed in Fig. 6, is provided with a lug 61 which has a portion adjacent to the plate extending away from the plane of the plate and merging into an end portion which is substantially parallel to the plane of the plate. This end portion of the lug 61 has fixed thereto a pin 62 that extends substantially parallel to the shaft 18 and projects through an elongated slot 63a formed in the free end of a lever arm 63. The opposite end of the lever arm 63 is provided with a hub which receives and is secured to, as by a setscrew, a shaft 64 rockably supported in suitable bearing openings formed in the bracket 19 and the portion 19b thereof and in other fixed supports beneath the bed plate (not shown) and extending parallel to but in a lower plane than the main shaft 18.

The shaft 64 has secured to it to the right of the sleeve 40 as viewed in Fig. 1 the hub 65a on one end of a vertically extending lever arm 65. The opposite and upper end of the lever arm 65 is of reduced pin-like formation 65b which projects into a cam groove 66 formed in the underside of a cam disk 67. The cam disk 67 is secured to or made integral with the lower end of a vertically extending stub shaft 68 that is rotatable in an opening formed in the bed plate 10.

The stub shaft 68 projects above the upper side of the bed plate and has secured to its upper end a feed dog height control knob 69 as well as a pointer finger 70, it being understood that the knob 69, finger 7ft, shaft 68 and cam 67 turn as a unit. The cam 67 on the underside of the bed plate and the finger 70 and knob 69 on the upper side of the bed plate hold the stub shaft 63 against axial movement.

It will further be understood that rotation of the knob 69 to rotate the cam 67 efiects rocking movement of the lever arm 65 due to the engagement of the pin-like portion 65b of the latter in the cam groove 66. This rocking movement of the lever arm 65 rocks the shaft 64, lever arm 63 and shifts the cam follower plate 60 in the cage in a direction transversely with respect to the shaft 13 to position the cam 58 in the opening 59 in either the drop feed position, i. e., the low end of the opening, or in intermediate positions or in maximum height position, i. e., the high end of the opening wherein the feed dog is in its most elevated position.

The bed plate 10 on its upper side may be provided with a scale 71 cooperating with the finger 70. The scale is calibrated in terms of the drop feed position, the maximum height position and five intermediate height positions of the feed dog and of the relationship of the cam 58 in the opening 59.

The horizontal component of the rotation of the cam 58 is wasted while thevertical component is utilized to produce the rise and fall of the feed dog as will be well understood. This rise and fall movement of the feed dog is occasioned by the upward and downward movement of the cage on the rocker arms 26 as is also the vertical adjusting movement of the feed dog and cage from drop feed position through the intermediate height positions to maximum height position and vice versa.

It will be understood that the grooves 34 and 35 in the bracket and in which the upper and lower ends 30 and 32 of the cage are located are of such width as to provide sufiicient clearance to permit the rocking movement imparted to the cage both for the rise and fall of the feed dog and for the vertical adjustment of the feed dog height. Of course the rise and fall movement of the feed dog combined with the linear movement imparted thereto by the elongated cam 41 furnishes the four motion feeding movement of the feed dog.

As already stated, since the opposite ends of the elongated cam 41 are 180 out of phase the horizontal movement imparted to the feed dog 15 when in raised or feeding position will be in opposite directions depending on which end of the elongated cam 41 the cam follower 41a is mounted. This provides for the forward and reverse feeding movements of the feed dog.

-As already stated, the cam 58 which imparts the rise and fall movement to the feed dog constantly rotates with the shaft 18 during the operation of the sewing machine. If it should be desired to have the four motion movement of the feed dog and idle movement as, for instance during darning or similar stitching operations, the operator merely turns the knob 69 to drop feed position to horizontally adjust the follower plate and to position the cam 58 in the low end of the opening 59. When it is desired that the four motion feed dog perform work then the operator can merely turn the knob 69 out of the drop feed position to any of the five intermediate height positions indicated on the scale 71 or to the maximum height position to elevate the feed dog in accordance with the requirements of the particular sewing operation being performed.

The mechanism described for imparting the four motion movements to the feed dog for regular feeding of the material being operated on by the machine can be utilized in conjunction with a second feed dog unit for imparting lateral feeding movement to the material for producing zig zag stitching as, for example, the mechanism shown in my copending application Serial No. 384,734, filed October 7, 1953.

In employing the feed mechanism illustrated and described herein and embodying the invention the operator will turn the knob 69 to the desired position to adjust the feed dog height. The operator will then loosen the knob 56 and swing the lever 48 to the desired position to the left or to the right of the zero mark on the scale 57 to provide for the proper length and direction of feed. The knob 56 will then be screwed down and clamped in the selected position and it will be understood that the elongated cam 41 will have been shifted axially relative to the cam follower 41a from the central position shown in Fig. 1 to one or the other side thereof the desired amount to produce the selected length and direction of linear feed movement to be imparted to the feed dog 15.

The operation of the machine will now cause the cage to be raised and lowered by the cam 58 with the rod 29 causing the arms 26 to rock with the shaft 27, it being understood that the ends of the rod 29 slide backwardly and forwardly in the longitudinal grooves 28 provided in the arms 26. This produces the rise and fall movement of the feed dog 15. The elongated cam 41 acting on the follower 41a imparts the horizontal movements to the cage which, it will be recalled, is free to slide lengthwise of the rod 29 and hence the linear feed movement of the feed dog 15 is obtained.

It will be noted that the operator can conveniently adjust through the feed dog height control the effect of the rise and fall movement of the feed dog and also can adjust through the knob 56 the amplitude of the linear feed movement of the feed dog. These adjustments can be obtained while the machine is operating and with great facility. It will be understood that the cam 67, due to theengagement of the pin b in the cam groove 66 acts as a lock to maintain the adjusted 'feed dog height until the operator desires to change the same by rotating the feed dog height control knob '69.

Although a preferred embodiment of the invention has been illustrated and described herein it will be understood that the invention is susceptible of various modifications and adaptations within the scope of the appended claims.

Having thus described my invention, I claim:

1. In a feeding mechanism for a sewing machine having a bed plate provided with a feed dog opening beneath the vertically reciprocating needle of the machine and a feed dog located in said opening; a rotatable shaft beneath the bed plate, a first cam rotatable with said shaft, a second cam rotatable with said shaft, a bracket beneath the bed plate, a cage through which said shaft extends and in which both of said cams are located, meansmountingsaid cage on said bracket for bodily linear horizontal and vertical movements of the cage,-

said cage having a portion cooperating directly with said first cam to produce the horizontal movement and a portion cooperating directly with said second cam to produce the vertical movement of the cage, and means operatively interconnecting said feed dog and cage whereby the horizontal and vertical movements of the cage are transmitted to the feed dog as linear feed and rise and fall movements.

2. In a feeding mechanism for a sewing machine as defined in claim 1 and wherein the means mounting said cage on said bracket includes a rockable connection for the vertical movement and a slidable connection for the horizontal movement.

3. In a feeding mechanism for a sewing machine as defined in claim 1 and wherein the means mounting said cage on said bracket includes spaced arms rockably connected to said bracket and each provided with a longitudinally elongated slot, and a rod having its opposite ends slidably supported in said slots in said arms, said cage being provided with a bore slidably receiving said rod.

4. In a feeding mechanism for a sewing machine as defined in claim 1 and wherein said first cam is an elongated cam having its axis of symmetry inclined relative to the axis of said shaft while said second cam is a disk eccentrically mounted on said shaft and having its periphery operatively associated with the second mentioned portion of said cage.

5. In a feeding mechanism for a sewing machine as defined in claim 1 and wherein said first cam is an elongated cam having its axis of symmetry inclined relative to the axis of said shaft and its opposite ends 180 out of phase, while a cam follower ring is mounted on said elongated cam for relative adjustment axially thereof and for rotation therewith with the periphery of said ring cooperating with the first mentioned portion of said cage.

6. In a feeding mechanism for a sewing machine as defined in claim 1 and wherein a sleeve is splined on said shaft for rotation therewith and movement axially thereof, while said first cam is an elongated cam fixedly mounted on said sleeve and having its axis of symmetry inclined relative to the axis of said shaft and is provided on its periphery with an axially extending key, and a cam follower ring is mounted on said elongated cam and is provided with a keyway cooperating with the key of said first cam, said first mentioned portion of said cage including spaced walls on opposite sides of said first cam and provided with vertical grooves receiving said ring and maintaining the same against movement axially of said shaft and said elongated cam but permitting rotative movement of said ring with said cam to impart horizontal movements to said cage.

7. In a feeding mechanism for a sewing machine as defined in claim 1 and wherein said shaft is provided with an elongated key, a first sleeve is mounted on said shaft and is provided with a keyway receiving said key, wherefore said sleeve will rotate with said shaft but be adjustable axially thereof, said first cam is an elongated cam fixedly mounted on said sleeve and having its axis of symmetry inclined relative to the axis of said shaft and provided on its periphery with an axially extending key, a cam follower ring is mounted for relative axial movement on said elongated cam and is provided with a keyway cooperating with the key on said cam, said first mentioned portion of said cage including spaced walls on opposite sides of said elongated cam and provided with vertical grooves receiving said ring and maintaining the same against movement axially of said shaft but permitting rotative movement of said ring with said cam to impart horizontal movements to said cage, said second cam being keyed on said shaft and rotatable therewith and in the form of an eccentric cam, said second mentioned portion of said cage having a recess, a cam follower plate slidably mounted in said recess for horizontal movement relative to said cage but movable therewith in a vertical direction, said cam follower plate being provided with an elongated opening inclined vertically downwardly and in which said second cam is located to contact the longitudinal sides of said opening, and means for moving the cam follower plate horizontally to adjust the position of the second cam in said opening and control the vertical height of the feed dog.

8. In a feeding mechanism for a sewing machine as defined in claim 7 and wherein said bracket is provided with aligned channels receiving the upper and lower portions of said cage, said channels being of such length and width compared to the upper and lower portions of said cage that the latter can move horizontally and can rock to impart linear feed and rise and fall movements to the feed dog.

9. In a feeding mechanism for a sewing machine having a bed plate provided with a feed dog opening beneath the vertically reciprocating needle of the machine and a feed dog located in said opening; a rotatable shaft beneath the bed plate, an eccentric cam disk keyed to said shaft, operative connections between said feed dog and said cam disk whereby rotation of said cam disk imparts rise and fall movements to said feed dog and including a cam follower plate provided with an elongated opening having its opposite ends located at different predetermined horizontal levels on said plate, said cam disk being located in said opening and contacting the opposite longitudinal edges thereof, means mounting said plate for movement horizontally and independently of the rise and fall movements of said operative connections and said feed dog, and means for horizontally moving said plate to adjust the position of said cam disk in said elongated opening to vary the vertical height of the feed dog in addition to the rise and fall movements imparted thereto.

10. In a feeding mechanism for a sewing machine as defined in claim 9 and wherein the means for horizontally moving said follower plate includes a feed dog height control member located on the upper side of the bed plate and operative connections between said member and said follower plate and extending beneath said bed plate.

11. In a feeding mechanism for a sewing machine having a bed plate provided with a feed dog opening beneath the vertically reciprocating needle of the machine and a feed dog located in said opening; a rotatable shaft beneath the bed plate, a cage beneath the'bed plate'and interconnected with said feed dog, means mounting said cage for bodily horizontal movements and for vertical rise and fall movements, an elongated cam having its axis of symmetry inclined relative to the axis of said shaft and its opposite ends predeterminedly out of phase, said cam being splined on said shaft, a cam follower ring on said elongated cam and movable relative thereto in an axial direction and contacting horizontally spaced portions of said cage, means for relatively moving said elongated cam and said ring in said axial direction to vary the amplitude of the horizontal movement of the cage and feed dog, a cam follower plate slidably supported by vertically spaced portions of said cage and provided with an elongated opening the opposite ends of which are at different horizontal levels on said follower plate, an eccentric cam disk keyed on said shaft and located in said elongated opening in engagement with the longitudinal edges thereof to impart rise and fall movements to said cage and feed dog, and means for sliding said follower plate relative to said cage to adjust the position of said cam disk in said elongated opening to vary the vertical position of the cage and the height of the feed dog in addition to the rise and fall movements imparted thereto.

12. In a feeding mechanism for a sewing machine as defined in claim 11 and wherein the means for relatively moving said elongated cam and follower ring includes a control element located above the bed plate and operative connections between said element and said elongated cam and ring located beneath the bed plate, while said means for sliding said follower plate includes a feed dog height control member located on the upper side of the bed plate and operative connections between said member and said follower plate and extending beneath said bed plate.

13. In a feeding mechanism for a sewing machine having a bed plate provided with a feed dog opening beneath the vertically reciprocating needle of the machine and a feed dog located in said opening; a rotatable shaft beneath the bed plate, an elongated cam having its axis of symmetry inclined relative to the axis of said shaft and its opposite ends predeterminedly out of phase, said cam being splined on said shaft for movement axially thereof and for rotation therewith, operative connections between said feed dog and said cam whereby the rotation of the cam will impart horizontal movements only to the feed dog and including a cam follower ring on said cam and movable relative thereto in an axial direction, a cage having horizontally spaced parallel portions engaged by said cam follower ring at points located diametrically opposite each other in the same horizontal plane, means for relatively moving said cam and ring in said axial direction to vary the amplitude of the horizontal movements of the feed dog, and means mounting said cage for horizontal movements in response to the rotation of said cam.

References Cited in the file of this patent UNITED STATES PATENTS 41,164 McCurdy Jan. 5, 1864 1,555,187 Cook et al Sept. 29, 1925 1,947,436 Russell Feb. 13, 1934 1,992,781 Smith Feb. 26, 1935 2,144,802 Hohmann Jan. 24, 1939 2,145,509 Ebert Jan. 31, 1939 2,651,274 Hohmann et a1. Sept. 8, 1953 2,672,112 Hale Mar. 16, 1954 FOREIGN PATENTS 914.715 France Oct. 16, 1946 

